The present invention relates to pipe couplings for coupling the ends of two pipes together and to methods of their manufacture.
The use of nonmetallic materials for drain pipes, such as those for use on bridges and buildings, has been attractive due to the ability of the pipes to resist corrosion and the pipes' light weight. Unsightly "rust stains" on exterior surfaces of bridges or buildings, characteristic of unprotected or compromised metallic components, are thereby eliminated. The use of nonmetallic materials for a conduit has also been attractive due to the ability of the conduits to resist corrosion and because such a conduit does not require cathodic protection. This is important because stray current in the ground, and induced currents within the conduit can cause severe corrosion to metal in a very short period of time due to galvanic attack. Fiberglass reinforced plastic (FRP) pipe has been used for sometime, to a limited extent, for both bridge drains and the conduit due to its corrosion resistance, light weight, and aesthetically pleasing appearance. A drawback to FRP pipe has been its relatively high cost compared to thin wall metallic pipe, especially at the joints.
Pipe couplings are used to couple or join the ends of two lengths of pipe together. Pipe couplings are basically sleeve-like devices, having a cylindrical passage therethrough for receiving the two pipes. In addition to coupling the ends of the pipes together, a pipe coupling provides seals around each pipe and prevents leakage from the joint.
Another typical application of pipe couplings occurs when a damaged section of pipe is replaced. A new pipe section is inserted in place of the old damaged section. Pipe couplings are used on each end of the new section of pipe to couple the section to the free ends of the in situ pipe.
There has been a need in the past for a cost effective, efficient and rapid means of connecting together pipe or tubing and for the repairing of faults or holes in such pipe or tubing without the necessity of cutting or dividing the pipe or tubing. Further, there has been a desire to provide a strong adhesive bond between the connector and the pipe or tubing to be bonded together or repaired.